A statement from the auction house said:" The collection will now remain intact and the planned public auction in September will no longer take place." The buyer wishes to remain private, but is committed to keeping the collection together.

"The Executors are delighted that their sister's estate can now be settled and are very confident the collection has found the perfect home," the statement said.

The collection reflects Issie's great passions and includes more than 50 hats by the renowned milliner, Philip Treacy, and more than 90 creations by the late Alexander McQueen - both designers whom she discovered, nurtured, championed and wore throughout her fashion career. There are also examples of John Galliano's early work, a number of pairs of Manolo Blahnik shoes, and designs by Hussein Chalayan and Giles Deacon. The collection also includes a selection of framed photographs of Issie, including portraits by world-renowned photographers such as Steven Meisel, David LaChapelle, Karl Lagerfeld, Mario Testino, Michael Roberts and Richard Burbridge.

"Isabella Blow fearlessly pursued perfection. Her genius lay in recognising talent in its raw state," said Christie's. "She was there through every stage of the process, and confidently earned her place on the front row of catwalk shows - a position she maintained for over two decades, culminating in Alexander McQueen's spring/summer 2008 catwalk show dedicated entirely to her memory."

Isabella Blow died on May 7, 2007, after drinking weedkiller, during a weekend at the family home, Hilles, in Gloucestershire.